Tube preamp reliability vs SS?

Good advice and comments  given above.  The tubes  use in preamplifier are typically  low signal and often run conservatively, they can last year's if of good quality.I have a Quicksilver preamp that I  use in a 2nd system, it's 's 23 years old and hasn't  missed a beat since the day  I bought it new. You can tailor the sound via  trying different  tubes. Simple  modification like capacitors or better fuses make a difference as well ďue to the simple  circuits of most tube preamps. My advice, get one that the  builder provides a high quality and  robust power supply. Power supplies  matter.
Good luck,
Charles,

Yep,
AL makes a good and specific observation, my reply was more general in nature. My original  (early version) Coincident Line Stage had 18 db of the gain. My DAC has an output of 3.2 volts and my speakers  are 94 dB sensitivity. I had too much  gain, couldn't go past 10 o'clock on the volume control. I replaced it with a 10 dB gain version  from Coincident and all was well, VC  range  now is  11-2  o'clock for most recordings. Total system gain has to be taken in to account.

Convenience is a very  legitimate  concern. For me the actual  sound quality and the  music  listening  experience  is the overwhelming criteria for choosing an audio component.